1. Field of the Invention
Embodiments of the present invention relate to a display device, and more particularly, to an electrophoretic display device. Embodiments of the present invention are suitable for a wide range of applications. In particular, embodiments of the present invention are suitable for preventing a characteristic degradation of a semiconductor switching device.
2. Description of the Related Art
If a material having electric charge is placed in DC electric field, the material peculiarly moves in accordance with electric charges, the size and shape of molecules and the like. Such a movement, i.e., a phenomenon in which materials are separated by the difference of movement, is named ‘Electrophoresis’. Recently, a display device using electrophoresis has been developed and attention has been paid thereto as a medium with which a conventional paper medium could be replaced.
The display using electrophoresis has been disclosed in U.S. Pat. No. 7,012,600 and U.S. Pat. No. 7,119,772. The electrophoretic display device of the related art updates a data through a reset period, a stabilization period, and a data writing period. In this case, micro capsules which are mixed with particles non-uniformly charged in accordance with an initial state, are initialized for the reset period. A black particle and a white particle within the micro capsules are entirely separated from each other to be stabilized the micro capsules at a bistable state for the stabilization period. A next data voltage to be updated is supplied for the data writing period. Approximately, 128 number of frame periods are comprised of the reset period, the stabilization period, and the data writing period. Such an electrophoretic display updates an image by the micro capsules through the 128 frame periods. After completing an update of the image, an image of the electrophoretic display is not changed until about 6 months after turning-off the power of the electrophoretic display.
On the other hand, after completing the update of the image, the electrophoretic display can be driven in a sleep-mode of low power consumption. The power of the electrophoretic display is not turned-off in the sleep-mode. A gate low voltage is applied to gate lines in the sleep-mode for a long time. A thin film transistor (hereinafter, referred to as “TFT”) having a gate electrode which is connected to a gate line, has a gate bias stress by a gate low voltage. Herein, the gate low voltage is supplied in the sleep-mode for a long time. Accordingly, the related art electrophoretic display has a problem in that a characteristics of the TFT is degraded in the sleep-mode to change a threshold voltage of the TFT or increase an off current.